Officials are probing how a 51-year-old highway bridge came to collapse in the Italian port city of Genoa yesterday, killing at least 26 people and injuring 16 others as it sent dozens of vehicles tumbling into a heap of concrete and twisted steel.

Same-sex marriage survey: How the yes voters reacted

'Yes' voters celebrated wildly in Sydney's Prince Alfred Park after learning a majority of Australians had voted in support of legalising same-sex marriage.

Thousands of supporters armed with flags, rainbow capes and 'Yes' badges had gathered to watch the Australian Bureau of Statistics announce the result shortly after 10am AEDT.

Before the announcement, the tension was noticeable.

But after head statistician David Kalisch had confirmed that over seven million Australians had voted in favour of yes – with 12.7 million Australians voting overall – the crowd erupted into celebration.

For one couple, speaking to nine.com.au, the result was about more than simply allowing same-sex couples to marry.

"It wasn't really about marriage equality, it was about asking whether Australians accept gay people as a whole … and they do," said Matthew.

"I think it's one of the highest percentages of 'yes' votes anywhere in the world, so after all that fuss Mr Turnbull has to do his job now otherwise he'll lose his prime ministership."